U.S. patent number 5,819,751 [Application Number 08/547,869] was granted by the patent office on 1998-10-13 for cigarette and method of making same.
This patent grant is currently assigned to R. J. Reynolds Tobacco Company. Invention is credited to Vernon Brent Barnes, Lloyd Harmon Hancock, Werner Hinz, Erwin Oesterling, Siegfried Schlisio, Donald Ross Wilkinson.
United States Patent |
5,819,751 |
Barnes , et al. |
October 13, 1998 |
Cigarette and method of making same
Abstract
Cigarettes and methods of making them, in which an insulated
fuel element is combined with a substrate assembly comprising a
substrate within a tube, combining a roll of tobacco with a plug of
tobacco paper, combining the fuel element/substrate assembly with
the tobacco/tobacco paper assembly, and combining the resulting
combination with a filter element to produce filter cigarettes.
Methods of constructing the various and preferred subassemblies are
also disclosed.
Inventors: |
Barnes; Vernon Brent (Clemmons,
NC), Wilkinson; Donald Ross (Clemmons, NC), Hancock;
Lloyd Harmon (Walnut Cove, NC), Oesterling; Erwin
(Glinde, DE), Schlisio; Siegfried (Geesthacht,
DE), Hinz; Werner (Lauenburg, DE) |
Assignee: |
R. J. Reynolds Tobacco Company
(Winston-Salem, NC)
|
Family
ID: |
26780643 |
Appl.
No.: |
08/547,869 |
Filed: |
October 25, 1995 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
89502 |
Jul 16, 1993 |
5469871 |
|
|
|
947021 |
Sep 17, 1992 |
|
|
|
|
Current U.S.
Class: |
131/194; 131/94;
131/359 |
Current CPC
Class: |
A24C
5/00 (20130101); A24C 5/471 (20130101); A24D
1/22 (20200101); A24D 3/17 (20200101) |
Current International
Class: |
A24C
5/00 (20060101); A24F 47/00 (20060101); A24C
5/47 (20060101); A24C 005/00 () |
Field of
Search: |
;131/194,359,360,352 |
References Cited
[Referenced By]
U.S. Patent Documents
|
|
|
3308832 |
March 1967 |
Stelzer et al. |
4714082 |
December 1987 |
Banerjee et al. |
4732168 |
March 1988 |
Resce et al. |
4756318 |
July 1988 |
Clearman et al. |
4782644 |
November 1988 |
Haarer et al. |
4793365 |
December 1988 |
Sensabaugh, Jr. et al. |
4802568 |
February 1989 |
Haarer et al. |
4807809 |
February 1989 |
Pryor et al. |
4827950 |
May 1989 |
Banerjee et al. |
4858630 |
August 1989 |
Banerjee et al. |
4870748 |
October 1989 |
Hensgen et al. |
4881556 |
November 1989 |
Clearman et al. |
4893637 |
January 1990 |
Hancock et al. |
4893639 |
January 1990 |
White |
4903714 |
February 1990 |
Barnes et al. |
4913169 |
April 1990 |
Templeton |
4917128 |
April 1990 |
Clearman et al. |
4928714 |
May 1990 |
Shannon |
4938238 |
July 1990 |
Barnes et al. |
4989619 |
February 1991 |
Clearman et al. |
5027836 |
July 1991 |
Shannon et al. |
5027837 |
July 1991 |
Clearman et al. |
5042509 |
August 1991 |
Banerjee et al. |
5052413 |
October 1991 |
Baker et al. |
5067499 |
November 1991 |
Banerjee et al. |
5076292 |
December 1991 |
Sensabaugh, Jr. et al. |
5099861 |
March 1992 |
Clearman et al. |
5101839 |
April 1992 |
Jakob et al. |
5105831 |
April 1992 |
Banerjee et al. |
5105837 |
April 1992 |
Barnes et al. |
5105838 |
April 1992 |
White et al. |
5183062 |
February 1993 |
Clearman et al. |
5247947 |
September 1993 |
Clearman et al. |
5469871 |
November 1995 |
Barnes et al. |
|
Foreign Patent Documents
|
|
|
|
|
|
|
0 339 690 |
|
Nov 1989 |
|
EP |
|
395280 |
|
Oct 1990 |
|
EP |
|
0 407 792 A2 |
|
Jan 1991 |
|
EP |
|
444553 |
|
Apr 1991 |
|
EP |
|
Other References
Tobacco Flavoring for Smoking Products, R. J. Reynolds Tobacco Co.
(1972). .
New Cigarette Prototypes that Heat Instead of Burn Tobacco,
"Chemical and Biological Studies On new Cigarette Prototypes That
Heat Instead of Burn Tobacco", R. J. Reynolds Tobacco Company.
.
U.S. Ser. No. 585,444, filed Sep. 20, 1990. .
U.S. application No. 07/882,209, filed May 14, 1992. .
U.S. application No. 07/800,679, field Nov. 27, 1990. .
U.S. application No. 07/722,993, filed Jun. 28, 1991. .
U.S. application No. 07/856,239, filed Mar. 25, 1992. .
U.S. application No. 07/601,551, filed Oct. 23, 1990. .
U.S. application No. 07/574,327, filed Aug. 28, 1990. .
U.S. application No. 07/710,273, filed Jun. 15, 1991..
|
Primary Examiner: Millin; V.
Parent Case Text
This is a continuation of application Ser. No. 08/089,502 filed on
Jul. 16, 1993 now U.S. Pat. No. 5,469,871, which is a
continuation-in-part of U.S. Ser. No. 07/947,021 filed on Sept. 17,
1992 now abandoned.
Claims
What is claimed is:
1. A method of manufacturing cigarettes comprising the steps
of:
(a) continuously providing an insulated fuel element;
(b) continuously providing a substrate section;
(c) continuously combining said insulated fuel element and
substrate section with an overwrap material to form a
fuel-substrate section;
(d) continuously providing a tobacco section;
(e) continuously aligning the substrate end of the fuel-substrate
section with the tobacco section and combining said sections with
an overwrap to form a fuel-substrate-tobacco assembly;
(f) continuously providing a filter element; and
(g) continuously combining the filter element with the tobacco end
of the fuel-substrate-tobacco assembly to form a filter
cigarette.
2. The method of claim 1, wherein the tobacco segment is tobacco
cut filler.
3. The method of claim 1, wherein said insulated fuel element is
provided by:
(a) extruding a continuous carbonaceous rod of a desired
configuration into a wrapper of continuous wrapper material;
and
(b) cutting the continuous insulated fuel rod into desired
lengths.
4. The method of claim 3, further including the step of drying the
insulated carbonaceous fuel elements to a desired moisture
content.
5. The method of claim 4, wherein the carbonaceous fuel elements
are dried to a moisture content of between about 12% and 14% by
weight.
6. The method of claim 5, wherein said drying step is carried out
in two separate stages during the cigarette manufacturing
process.
7. The method of claim 1, wherein said continuous insulated fuel
element is cut into insulated fuel rods having 6-up lengths, and
further including the steps of:
(a) cutting the 6-up insulated fuel rod into insulated fuel
elements;
(b) separating the insulated fuel elements;
(c) inserting a 2-up substrate section between the insulated fuel
elements;
(d) aligning and abutting the 2-up substrate section and the
insulated fuel elements; and
(e) overwrapping the 2-up substrate section and the insulated fuel
elements with a wrapper to form a 2-up fuel substrate section.
8. The method of claim 7, further including the steps of:
(a) dividing the 2-up fuel substrate section at its mid-point;
(b) separating the fuel substrate sections;
(c) inserting a 2-up tobacco section between the fuel substrate
sections;
(d) aligning and abutting the end of the fuel substrate section
with the 2-up tobacco section; and
(e) overwrapping the assembled components to form a 2-up tobacco
fuel unit.
9. The method of claim 8, wherein said filter element is provided
in a 2-up length, and further including the steps of:
(a) dividing the 2-up tobacco fuel unit at its mid-point;
(b) inserting a 2-up length filter between the divided tobacco fuel
units, aligning and abutting the same;
(c) overwrapping the assembled components with a wrapper to form a
2-up filter cigarette; and
(d) cutting the 2-up filter cigarette at the mid-point of the
filter to form two individual filter cigarettes.
Description
FIELD OF THE INVENTION
The present invention is directed to cigarettes and a method of
manufacturing the same. Many improved cigarettes have been
proposed. For example, numerous references have proposed cigarettes
which generate a flavored vapor and/or a visible aerosol. Many of
such cigarettes have employed a combustible fuel source to provide
an aerosol and/or to heat an aerosol forming material. See, for
example, the background art cited in U.S. Pat. No. 4,714,082 to
Banerjee et al.
BACKGROUND OF THE INVENTION
The present invention relates to cigarettes, and in particular to
those cigarettes having a short fuel element and a physically
separate aerosol generating means. Cigarettes of this type, as well
as materials, methods and/or apparatus useful therein and/or for
preparing them, are described in the following U.S. Pat. Nos.
4,714,082 to Banerjee et al., 4,732,168 to Resce; 4,756,318 to
Clearman et al., 4,782,644 to Haarer et al., 4,793,365 to
Sensabaugh et al., 4,802,568 to Haarer et al., 4,807,809 to Pryor
et al., 4,827,950 to Banerjee et al., 4,858,630 to Banerjee et al.,
4,870,748 to Hensgen et al., 4,881,556 to Clearman et al.,
4,893,637 to Hancock et al.; 4,893,639 to White; 4,903,714 to
Barnes et al.; 4,917,128 to Clearman et al.; 4,928,714 to Shannon;
4,938,238 to Barnes et al.; 4,989,619 to Clearman et al.; 5,027,836
to Shannon et al.; 5,027,839 to Clearman et al.; 5,042,509 to
Banerjee et al.; 5,052,413 to Baker et al.; 5,060,666 to Clearman
et al.; 5,065,776 to Lawson et al.; 5,067,499 to Banerjee et al.;
5,076,292 to Baker et al.; 5,099,861 to Clearman et al.; 5,101,839
to Jakob et al.; 5,105,831 to Banerjee et al.; 5,105,837 to Barnes
et al., and 5,119,837 to Banerjee et al., 5,183,062 to Clearman et
al., and U.S. Pat. No. 5,203,355 to Clearman, et al., as well as in
the monograph entitled Chemical and Biological Studies of New
Cigarette Prototypes That Heat Instead of Burn Tobacco, R. J.
Reynolds Tobacco Company, 1988 (hereinafter "RJR Monograph"). These
cigarettes are capable of providing the smoker with the pleasures
of smoking (e.g., smoking taste, feel, satisfaction, and the like).
Such cigarettes typically provide low yields of visible sidestream
smoke as well as low yields of FTC tar when smoked.
The cigarettes described in the aforesaid patents and/or
publications generally employ a combustible fuel element for heat
generation and an aerosol generating means, positioned physically
separate from, and typically in a heat exchange relationship with
the fuel element. Many of these aerosol generating means employ a
substrate or carrier for one or more aerosol forming materials,
e.g., polyhydric alcohols, such as glycerin. The aerosol forming
materials are volatilized by the heat from the burning fuel element
and upon cooling form an aerosol. Normally, the fuel elements of
such smoking articles are circumscribed by an insulating
jacket.
SUMMARY OF THE INVENTION
The present invention is directed to improvements in cigarettes
having a short carbonaceous fuel element and a physically separate
aerosol generating means as well as improved methods of
manufacturing such cigarettes.
Preferred cigarettes of the present invention include a short
extruded carbonaceous fuel element which is circumscribed by an
insulating jacket. Normally, the fuel element has one or more
longitudinal grooves extending along its outer periphery. Such
grooves assist in lighting of the fuel element and allow heated air
to flow along the periphery of the fuel element. The grooves also
tend to assist in retaining the fuel element within the jacket.
The length of the fuel element is typically from 3 mm to about 20
mm, preferably about 5 mm to about 16 mm and most preferably about
6 mm to about 12 mm in length prior to burning.
The fuel element is retained within the cigarette of the present
invention by an insulating jacket. Preferably the insulating jacket
circumscribes the entire longitudinal periphery of the fuel
element, although it may extend beyond each end of the fuel
element, effectively recessing the fuel element, separating it from
the other components of the cigarette. The preferred resilient
nature of the insulating jacket allows it to extend into any
grooves on the periphery of the fuel element. The insulating jacket
also aids in retaining heat and permits radial atmospheric air to
flow to the fuel element during use.
In one especially preferred embodiment, the resilient insulating
means comprises a fibrous material which circumscribes the
longitudinal periphery of the fuel element. The fibrous material
may comprise glass fibers (Owens-Corning "C" glass is especially
preferred), a tobacco filler/glass fiber mixture, gathered or
shredded tobacco paper, gathered or shredded carbon paper, tobacco
cut filler, or the like.
Typically a carbonaceous mass is extruded into a continuous rod of
a desired shape, laid directly onto a ribbon of insulating material
which is circumscribed by a wrapper to form a jacketed continuous
rod. The jacketed continuous rod is cut into appropriate length
useful in the manufacturing method of the present invention. During
manufacturing, as aqueous liquid such as tap water is applied in an
appropriate amount to the carbonaceous rod and/or insulating
material which assists in bonding the carbonaceous rod to the
insulating material upon drying to an appropriate moisture.
The cigarette further includes an aerosol generating means which
includes a substrate and at least one aerosol forming material. A
preferred aerosol generating means includes an aerosol forming
material (e.g., glycerin), tobacco in some form (e.g., tobacco
powders, tobacco extract or tobacco dust) and other aerosol forming
materials and/or tobacco flavoring agents, such as cocoa, licorice
and sugar. The aerosol forming material generally is carried in a
substrate material, such as a reconstituted tobacco cut filler or
by a substrate such as tobacco cut filler, gathered paper, gathered
tobacco paper, or the like.
Preferably the substrate is a reconstituted tobacco cut filler cast
sheet material, which is formed into a continuous rod or substrate
tube assembly on a conventional cigarette making machine. Typically
the overwrap material for the rod is a barrier material such as a
paper foil laminate. The foil serves as a barrier, and is located
on the inside of the overwrap.
Alternatively, the substrate may be a gathered paper formed into a
rod or plug. When the substrate is a paper-type material, it is
highly preferred that such substrate be positioned in a spaced
apart relationship from the fuel element. A spaced apart
relationship is desired to minimize contact between the fuel
element and the substrate, thereby preventing migration of the
aerosol forming materials to the fuel, as well as limiting the
scorching or burning of the paper substrate. The spacing is
normally provided during manufacture of the cigarette in accordance
with one method of making the present invention. Appropriately
spaced substrate plugs are overwrapped with a barrier material to
form a substrate tube assembly having spaced substrate plugs
therein. The substrate tube assembly is cut between the substrate
plugs to form substrate sections. The substrate sections include a
tube with a substrate plug and void(s), preferably at each end.
The barrier material for making the tube aids in preventing
migration of the aerosol former to other components of the
cigarette. The barrier material forming the tube is a relatively
stiff material so that when formed into a tube it will maintain its
shape and will not collapse during manufacture and use of the
cigarette.
An appropriate length of the jacketed fuel element is combined with
a substrate section or substrate tube assembly by a wrapper
material, which has a propensity not to burn, to form a
fuel/substrate section. In preferred embodiments of the cigarettes,
the wrapper typically extends from the mouthend of the substrate
section, over a portion of the jacketed fuel element, whereby it is
spaced from the lighting end of the fuel element. The wrapper
material assist in limiting the amount of oxygen which will reach
the burning portion of the fuel element during use, preferably
thereby causing the fuel element to extinguish after an appropriate
number of puffs. In especially preferred embodiments of the
cigarette, the wrapper is a paper/foil/paper laminate. The foil
provides a path to assist in dissipating or transferring the heat
generated by the fuel element during use. The jacketed fuel element
and the substrate section are joined by the overwrap.
A tobacco section is preferably formed by a reconstituted tobacco
cut filler rod, made on a typical cigarette making machine, and cut
into appropriate lengths. A filter rod is formed and cut into
appropriate lengths for joining to the tobacco section to form a
mouthend section. The fuel/substrate section and the mouthend
section are joined by aligning the reconstituted ends of each
section, and overwrapped to form a cigarette.
When a paper substrate is used, a tobacco paper rod and a
reconstituted cut filler rod are preferably formed and cut into
appropriate lengths and joined to form a tobacco section.
The tobacco section and the fuel/substrate section are joined by
aligning the tobacco paper plug end of the tobacco section with the
substrate end of the fuel/substrate section and joining the
sections with a wrapper which extends from the rear end of the
tobacco roll to an appropriate length past the junction of the two
sections for forming the tobacco roll/fuel assembly. The tobacco
roll/fuel assembly is then joined to a filter by a tipping
material.
In the cigarettes of the present invention convective heat is
preferably the predominant mode of energy transfer from the burning
fuel element to the aerosol generating means disposed
longitudinally behind, the fuel element. When a foil/paper laminate
is used as an overwrap to join the fuel/substrate section; some
heat may be transferred to the substrate by the foil layer. As
described above, the heat transferred to the substrate volatilizes
the aerosol forming material(s) and any flavorant materials carried
by the substrate, and, upon cooling, these volatilized materials
are condensed to form a smoke-like aerosol which is drawn through
the cigarette during puffing, and which exits the filter piece.
As used herein, the term "aerosol" is meant to include vapors,
gases, particles, and the like, both visible and invisible, and
especially those components perceived by the smoker to be
"smoke-like," formed by the action of heat generated by the fuel
element upon materials contained within the aerosol generating
means, or elsewhere in the smoking article.
As used herein, the term "carbonaceous" means comprising primarily
carbon.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 3 illustrate in sectional view, two embodiments of
cigarettes prepared in accordance with the present invention. In
these depictions, the thickness of the various overwraps has been
increased, for ease in viewing and clarity of structure.
FIG. 1A is an end view of the cigarette shown in FIGS. 1 and 3.
FIGS. 2A, 2B and 2C illustrate a flow diagram of one preferred
method for manufacturing the cigarette embodiments of the present
invention illustrated in FIG. 1 and FIG. 1A.
FIGS. 4A, 4B and 4C illustrate a flow diagram of one preferred
method of manufacturing the cigarette of the present invention
illustrated in FIG. 3.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
In FIGS. 1, 1A and 3, embodiments of the cigarette 15 of the
present invention are illustrated. The cigarette includes a fuel
element 10 circumscribed within a retaining jacket of insulating
material 12 (e.g., jacketed fuel element 18). The insulating and
retaining jacket material 12 comprises glass fibers.
As illustrated in FIG. 1A, the fuel element 10, which preferably is
an extruded carbonaceous material, is generally cylindrical in
shape and has a plurality of longitudinally extending peripheral
channels 11.
The insulating and retaining jacket 12 has an intermediate layer 14
of tobacco paper positioned between two layers of glass fibers.
Surrounding the insulating and retaining jacket 12 is paper wrapper
13. Wrapper 13 may comprise one or more layers which provide
appropriate porosity and ash stability characteristics.
Situated longitudinally behind the jacketed fuel element 18 is an
aerosol generating means. In FIG. 1, the substrate plug 22,
advantageously is made from a gathered web of cellulosic material,
(e.g., paper or tobacco paper) having a paper overwrap 24. The
substrate 22 holds one or more aerosol forming materials (such as
glycerin), a form of tobacco (such as tobacco powder, extract or
dust), and flavor components, which are volatilized by heat
generated by the burning of the fuel element. The substrate 22 is
positioned in a barrier tube 26 so that voids 28 and 30 are
provided on either end of the substrate plug 22 to form a substrate
section or component 20. The spaced apart relationship between the
substrate plug and fuel element assists in preventing the substrate
from scorching or burning during use of the cigarette, and, along
with the barrier tube, aids in preventing migration of the aerosol
forming material(s) from the substrate to the fuel element and
other components of the cigarettes.
In FIG. 3, the substrate 22 is advantageously made from a
reconstituted tobacco cast sheet cut filler material. Such
substrates are described in U.S. Pat. application Ser. No.
07/800,679, filed 27 Nov., 1991, which is incorporated herein by
reference.
Besides the above-described substrate rods, other substrate
material rods can be shredded puffed grain (e.g., puffed rice), or
a tobacco/puffed grain blend, which has an aerosol forming material
and binder applied to the puffed grain. The aerosol forming
material and binder may be heated to form a gel which is carried by
the substrate rod. The shredded and puffed grain carrying the
aerosol forming material may be mixed with tobacco dust and formed
into overwrapped rods using a cigarette making machine.
Examples of preferred aerosol forming materials include the
polyhydric alcohols (e.g., glycerin, propylene glycol, triethylene
glycol and tetraethylene glycol), the aliphatic esters of mono-,
di-, or poly-carboxylic acids (e.g., methyl stearate, dimethyl
dodecandioate and dimethyl tetra decanedioate), Hystar TPF
available from Lonza, Inc., and the like, as well as mixtures
there. For example, glycerin, triethylene glycol and Hystar TPF can
be mixed together to form an aerosol forming material. Also, a
propylene glycol/glycerin mixture is used.
Examples of other aerosol forming materials include volatile
flavoring agents and tobacco flavor modifiers. Volatile flavoring
agents include menthol, vanillin, cocoa, licorice, organic acids,
high fructose corn syrup, and the like. Various other flavoring
agents for smoking articles are set forth in Leffingwell et al.,
Tobacco Flavoring For Smoking Products (1972) and in European
Patent Publication No. 407,792. Tobacco flavor modifiers include
levulinic acid, metal (e.g., sodium, potassium, calcium and
magnesium) salts of levulinic acid, and the like.
Circumscribing the jacketed fuel element and spaced from the
lighting end thereof is a non-burning or foil-backed (e.g.,
aluminum or other metal) paper wrapper 32, which also extends over
the substrate section 20. Wrapper 32 is preferably a non-wicking
material which prevents the wicking of the aerosol forming
material(s) from the substrate 22 to the fuel element 10, the
insulating jacket 12, and/or from staining of the other components
of the cigarettes. This wrapper also minimizes or prevents
peripheral air (i.e., radial air) from flowing to the portion of
the fuel element disposed longitudinally behind its front edge,
thereby causing oxygen deprivation and preventing excessive
combustion. While not preferred, wrapper 32 may extend over the
burning end of the fuel element 10 (or beyond the same) and be
provided with a plurality of perforations (not shown) to allow
controlled radial air flow to the burning segment of the fuel
element to support combustion.
The void space 30 of the cigarette of FIG. 1 acts as a cooling and
nucleation chamber wherein the hot volatile materials exiting the
substrate cool down and form an aerosol. If desired, the void space
30 may be filled with a roll of gathered or shredded tobacco paper
(not shown). The presence of tobacco paper within the void space
contributes tobacco flavors to the aerosol.
Positioned rearwardly and adjacent to the substrate section 20 is a
tobacco section or component 34. In FIG. 1, the tobacco section
includes a tobacco paper plug 36 with a paper wrapper 37, such as
KC P-3284-19, available from Kimberly Clark ("KC"), of Neenah,
Wis., and a roll of tobacco cut filler 38 circumscribed by a paper
wrapper 39. The tobacco section 34 is overwrapped by a paper
wrapper 40. The tobacco paper plug end of the tobacco section 34
abuts the substrate section and is combined thereto by an overwrap
paper 42. The overwrap paper 42 extends from the rear end of the
tobacco roll 38 to slightly forward of the junction between the
tobacco paper plug 36 and the substrate section 20 to form a
tobacco/fuel assembly 45.
If desired, a carbon filled sheet containing a flavorant such as
menthol can be substituted for or used in conjunction with the
tobacco paper plug.
In FIG. 3, the tobacco section 34 is a roll of reconstituted
tobacco cut filler 38, circumscribed by paper wrapper 39.
Positioned at the extreme mouth end of the cigarette is a
low-efficiency filter element 44 including a filter material, such
as a gathered web of non-woven polypropylene fiber, cellulose
acetate, or the like, overwrapped with a plug wrap 47. In FIG. 1,
the filter abuts the tobacco roll 38 of the tobacco/fuel section 45
and is combined thereto by tipping wrapper 46. In FIG. 3, the
filter abuts the tobacco section 34, and is combined with a tipping
paper or tipping wrapper 46.
In use, the smoker lights fuel element 10 which burns to produce
heat. During draw, air passes along the periphery of the burning
portion of the fuel as well as through the retaining and insulating
jacket 12. The drawn air is heated by contacting the burning
portion of the fuel element and by heat radiated from the fuel
element. The heated air transfers heat by convection to the
substrate 22. The transferred heat volatilizes the aerosol forming
and flavor materials carrier by the substrate. The volatilized
material within the hot drawn air exits the substrate. As the
volatilized material cools during passage through the remainder of
the substrate, through void space 30 (if present), and through the
tobacco section, an aerosol is formed. The aerosol passes through
the tobacco section, and the tobacco paper plug 36 (if present),
absorbing tobacco flavors, and passes through the filter material
44, and into the mouth of the smoker.
Since the rear end portion of the fuel element does not burn during
use of the cigarette, the fuel element remains securely in the
cigarette and does not have a tendency to become dislodged from the
cigarette during use. When the fuel element self-extinguishes and
no longer generates heat, the cigarette is disposed of.
Referring to FIGS. 2A, 2B and 2C, there is shown a flow diagram of
one preferred method for manufacturing the cigarette embodiments of
the present invention illustrated in FIG. 1 and FIG. 1A. The method
involves separately manufacturing the various cigarette components
such as the jacketed fuel element, substrate section, tobacco
section and filter followed by combining the individually prepared
components in a specified sequence.
As illustrated, a substrate rod 50 is formed by gathering a
paper-type web materials into a continuous cylindrical rod and
overwrapping the continuous rod with a wrapping material. The
substrate material is preferably both embossed and gathered to form
the substrate rod. The substrate rods can be provided (i) using the
apparatus described in U.S. Pat. No. 4,807,809 to Pryor, et al.;
(ii) using the apparatus described in U.S. patent application Ser.
No. 585,444, filed Sept. 20, 1990; or (iii) using a rod forming
unit available as CU-10, CU-20 or CU-20S from Decoufle s.a.r.b.,
together with a KDF-2 rod making apparatus from Korber & Co.,
A.G., Hamburg, Germany (Korber). The web material is typically
provided with a plurality of embossed lines parallel to the machine
direction so that the web gathers in a more uniform pattern.
Preferred substrates retain the aerosol forming material when not
in use, and release the aerosol forming material during the smoking
period. One preferred type of substrate is a non-woven sheet-like
material such as paper, carbon paper or tobacco paper. Typically,
such substrates are provided as cylindrical rods including an
embossed and gathered web of paper circumscribed by an outer
wrapper. Preferred substrates of this type are described in U.S.
patent application Ser. No. 07/882,209, filed 13 May, 1992, the
disclosure of which is incorporated herein by reference. Other
types of web substrate materials include laminates, such as
paper/foil laminates.
In particular, the continuous web of substrate material is
embossed, gathered into a plurality of longitudinally extending
folds while having the aerosol forming material continuously
applied to the center thereof, to form a rod which is then
circumscribed by the outer wrapper.
The substrate may also be formed of a rod having a concentric
configuration in which the center core is formed of a paper
material which will absorb and retain the aerosol forming material
and an outer rind of barrier material which circumscribes the core
to assist in limiting migration of the aerosol former.
The outer wrapper which circumscribes the gathered substrate
material is preferably a paper material and can be coated or
treated with a material so as to limit migration of the aerosol
forming material. An example of such a coating is Hercon 70
available from Hercules, Inc., or a metal foil.
The substrate web is gathered to form substrate rods such that the
cross-sectional void area of the rod typically ranges from about 5
to about 30 percent, generally from about 8 to about 25 percent,
and often about 10 to about 20 percent. The cross-sectional void
area (i.e., that area provided by passageways when the rod is
viewed end-on) typically can be determined using an image analysis
technique using an IBAS Image Analyzer available from Carl Ziess,
Inc.
An aerosol forming material may be applied to the substrate
material prior to forming or may be introduced into the substrate
web through a tube centered in the gathering garniture of the KDF
rod making apparatus 53. A metering pump is used to provide a
specified amount of aerosol forming material into the substrate
web. The continuous substrate rod is cut into substrate rods 50
approximately 60 mm in length and fed into suitable conveying means
for conveying the rods to the next assembly station. Suitable
conveying means for the various subassemblies described herein
include batch conveyors, such as an HCF 80 tray filler, available
from Korber, or continuous conveyors, such as pneumatic or other
conveyor apparatus known in the art.
A carbonaceous fuel rod 51 is formed utilizing a screw or a piston
type extruder 55. A preferred carbonaceous mixture can be prepared
by admixing up to 95 parts carbonaceous material, up to 20 parts
binder and up to 20 parts of tobacco (e.g., tobacco dust and/or a
tobacco extract) and with sufficient water to form a paste, and
extruding the paste into the desired form. The water can
advantageously be provided in the form of an aqueous Na.sub.2
CO.sub.3 solution. See also U.S. Pat. No. 07/722,993, filed 28
Jun., 1991, the disclosure of which is incorporated herein by
reference. See also the U.S. Patents and patent applications cited
as background above, for other examples of carbonaceous
mixtures.
Extruded carbonaceous rods can be provided as follows. Carbon
particles are provided in a particulate form by ball milling
techniques. Tobacco laminae can also be ball milled to a fine
particle size (e.g., 5 to 15 .mu.m, preferably 7 to 12 .mu.m
--average) and mixed with the carbon particles. Other fuel element
components or additives (e.g., calcium carbonate particles or
graphite) can be blended with the carbon particles or mixture of
carbon and tobacco particles. The particles then are physically
mixed with dry, powdered binding agent. Then, the resulting dry
blend is physically mixed while an atomized spray of water is
applied thereof. The resulting damp mix typically exhibits a
moisture content of about 40 to about 40 weight percent wet basis,
preferably 32 to 38 and most preferably 34-36. The stated moisture
content will depend on the type of extruder used and to some extent
on the configuration of the carbonaceous mixture. If desired, water
soluble materials or additives (e.g., tobacco extracts, salts, and
the like) can be incorporated into the mix by dissolving such
materials or additives in the water.
The damp mix is preferably extruded using a compounding extruder
(e.g., a double screw compounding extruder). Optionally, the damp
mix is extruded into a premixed billets using a Baker-Perkins
MP-50-35 DE XLT extruder; and then the billets are extruded into
the desired shape using a ram piston extruder, such as an HET-120A
from Hydramet American Inc. The mix may also be extruded into the
desired shape using a double screw compounding extruder equipped
with a screw including a series of forward screw segments, paddle
segments and feed screw segments.
Peripheral grooves are included in the finished fuel elements
during extrusion. It is preferred that the grooves be deeper than
their width, advantageously the depth should be up to about twice
(2.times.) the width. Typical widths for grooves on the fuel
elements of this invention are from about 0.25 mm to about 1.5 mm,
preferably from about 0.5 mm to about 1.0 mm. The depths of these
grooves is generally within the range of about 1 mm to about 1.5
mm. The grooves may have either a rounded (concave or convex)
bottom, or a square or rectangular bottom. The preferred shape is a
concave bottom.
The extruded mix exits a die as a continuous extrudate having the
desired cross-sectional shape, and is deposited onto an
airfoil.
The extruded continuous carbonaceous fuel rod 51 is wrapped in an
insulating material and outer paper wrapper using a modified KDF 56
as described in U.S. Pat. No. 4,893,637, to form a wrapped
fuel/insulator assembly 52. A preferred extrusion and wrapping
process is described in U.S. patent application Ser. No. 07/856,239
filed Mar. 25, 1992, the disclosure of which is incorporated herein
by reference.
The insulating material preferably will permit drawn air to pass
therethrough, and will assist in holding the fuel element in place.
In some embodiments, the insulating and/or retaining material is
compressed around the fuel element, thereby ensuring a good, stable
positioning and snug fit of the fuel element therein. Typically, in
preferred embodiments the pectin binder in the glass fiber
insulating material is reactivated by applying water so that the
insulating material will adhere to the fuel element upon
drying.
The composition of the insulating and/or retaining material which
surrounds the fuel element can vary. This material is preferably
one which has a tendency not to combust or a material which
combusts but does not disintegrate. Examples of suitable materials
include glass fibers and other materials of the type described in
U.S. patent application Ser. No. 07/601,551, filed Oct. 23, 1990;
European Patent Publication No. 366,690; and pages 48-52 of the
monograph entitled, Chemical and Biological Studies of New
Cigarette Prototypes That Heat Instead of Burn Tobacco, R. J.
Reynolds Tobacco Co. (1988).
Examples of other suitable insulating and/or retaining materials
are glass fiber and tobacco mixtures such as are described in U.S.
Pat. No. 4,756,318 to Clearman et al. and U.S. Pat. No.
5,065,776.
As illustrated in FIGS. 1 and 1A, the insulating and/or retaining
material which surrounds the fuel element is circumscribed by a
paper wrapper. This paper wrapper may comprise one or two layers,
which may vary in air permeability and ash stability
characteristics. Papers having these characteristics are described
in U.S. Pat. No. 4,938,238 to Barnes et al. and U.S. patent
application Ser. No. 07/574,327 by Barnes et al. An example of a
suitable outer paper wrapper is available as P-3122-153 from
Kimberly-Clark Corp. and No. 15456 Ecusta, a division of P. H.
Gladfelder.
Upon leaving the extrusion process, the moisture content of the
carbonaceous fuel rod 51 is about 30 to 38 percent by weight. After
the fuel is overwrapped, the wrapped continuous fuel rod is cut to
form a 6-up jacketed fuel rod 52 approximately 72 mm in length. If
desired, at this point in the manufacturing process the jacketed
fuel rod may be dried to reduce the moisture content of the
carbonaceous rod. Preferably the moisture content should be
maintained at an appropriate level so that the carbonaceous rods
can be cut during subsequent manufacturing steps without fracturing
or chipping. Normally, a moisture content between 38 and 12 percent
is acceptable. The dryer used (not shown) can be a passive drying
apparatus such as a timed accumulator system (e.g., a Resy
available from Korber, or S-90, available from G.D Societe Per
Azioni, Bologna, Italy, optionally in a humidity controlled
environment) or a positive drying system such as a hot air blower
system. The jacketed fuel rods are fed to a tipping unit 60 such as
a Max R-1 available from Korber.
The 60 mm substrate rods 50 are fed into a plug tube combining
apparatus such as a Mulfi R-1, consisting of a GC unit 62 and a
KDF-2D unit 63 available from Korber. The substrate rods are cut
into 10 mm plugs, which are then graded, aligned and spaced at
intervals about 10 mm in the GC unit. Pairs of spaced 10 mm plugs
are transferred to the KDF-2D unit at intervals of about 12 mm and
aligned. The spaced plugs 22 are overwrapped with a wrapper 26
(FIG. 1) which forms a tube having substrate plugs spaced at 10 mm
and 12 mm intervals. The tube is cut through about the midpoint of
the 10 mm spaces to form a 2-up substrate tube 64 about 42 mm in
length having a void space at each end approximately 5 mm in
length, two substrate plugs approximately 10 mm in length and a
void space 69 of about 12 mm between the two substrate plugs.
The overwrap material is preferably a foil/paper laminate. The foil
layer providing an additional barrier to aid in preventing
migration of the aerosol forming material. The wrapper material is
designed so that upon forming a tube that will not bend or collapse
during the manufacturing process or during use of the
cigarette.
Advantageously, the KDF-2D 63 of the plug tube combiner is directly
linked to the tipper 60 so that the substrate tubes 64 are
transferred to an appropriate drum on the tipper. The tipper 60
also receives the jacketed fuel rods 52 from the previously
described fuel extrusion process. In the tipper 60, the 72 mm
jacketed fuel rods, or 6-up jacketed fuel rods are cut into lengths
of about 12 mm to form jacketed fuel elements 18. The jacketed fuel
elements are then graded, aligned with a pair being spaced and
positioned on opposite ends of a substrate tube 64 with a jacketed
fuel element 18 adjacent to the void 28 and on each end of the
substrate tube 64. The aligned components are overwrapped with a
wrapper or tipping material 32 (FIG. 1) to form a 2-up
fuel/substrate section 65, approximately 66 mm in length, having a
fuel element 18 at each end, two void spaces 28, two substrate
plugs 22 and a center void space 69. Preferably, the tipping
material 32, is about 54 mm in length by about 26 mm in width and
is applied to the 2-up fuel substrate section 65 so that
approximately 6 mm of each of the jacketed fuel elements extend
beyond the edge of the tipping material and, thus is not covered by
the tipping material. The tipping material is preferably a
paper/foil/paper laminate.
When the fuel/substrate section 65 exits the tipper 60, the section
passes through drying stage 66 to dry the carbonaceous fuel
elements. Drying can be accomplished in a passive manner using an
accumulator such as a Resy or S-90 optionally in a humidity
controlled environment or a positive heating process. The heating
process should not be so great that the aerosol forming material
and other flavorants will be volatilized off the substrate.
Preferably, the carbonaceous fuel is dried to a moisture content of
approximately 12 to 14 percent by weight. If desired, the drying
stages can be eliminated and relocated since they depend on the
moisture content of the extruded rod and the time lapse between the
different stages in the manufacturing process.
Preferably, simultaneously with the manufacture of the
fuel/substrate section 65, tobacco section 34 (FIG. 1) of the
cigarette 5 is being made, as shown in FIG. 2B. A continuous
tobacco rod is formed on a cigarette making machine 71 such as a
Protos VE/SE available from Korber using a cut filler material such
as tobacco, reconstituted tobacco or the like. The continuous
tobacco rod is cut into lengths of 120 mm forming tobacco rolls or
rods 70.
The tobacco cut filler rod is joined to a plug of tobacco paper,
shown at 34 in FIG. 1. The tobacco paper plug is obtained from a
continuous tobacco paper rod as described in prior U.S. Pat. No.
4,807,809. The tobacco paper rods are wrapped with suitable
cigarette paper using a web feeder apparatus and a modified KDF 77,
as therein described, and are cut into tobacco paper rods 75 about
80 mm in length.
The 120 mm tobacco rod 70 and the 80 mm tobacco paper rod 75 are
fed into the hoppers of a plug tube combiner such as a Mulfi R-2,
including a GC unit 79 and a KDF-2D 80. The tobacco rod and tobacco
paper rods are cut into segments of 40 mm and 20 mm, respectively.
The segments are graded and aligned in the GC unit in an
alternating abutting position upon transfer to the KDF-2D where the
rod segments are overwrapped with paper and cut into cut
filler/tobacco paper assemblies or 4-up tobacco sections 81 having
a center 20 mm tobacco paper rod 86 between a pair of 40 mm tobacco
cut filler segments 82 with 10 mm tobacco paper segment 83 on each
end.
As shown in FIG. 2C, the 4-up tobacco section 81 is fed into a
tipping unit 85 such as a Max R-2 tipper available from Korber. In
the tipper, the 4-up section 81 is cut at its midpoint through
tobacco paper segment 86 to form a 2-up tobacco section 87 having a
40 mm tobacco roll center segment and 10 mm tobacco paper segments
at each end. The 2-up tobacco sections 87 are graded and
aligned.
The 2-up fuel/substrate sections 65 are fed to tipper 85 which cuts
the 2-up fuel substrate section 65 at its mid-point through the
substrate tube, grades, aligns and positions the two halves on
opposite sides of a tobacco section 87 with the void 30 (FIG. 1) of
the fuel/substrate section adjacent the tobacco paper segments 83.
This assembly of components is then overwrapped with a suitable
wrapper 42 (FIG. 1) to form 2-up tobacco/fuel units 88
approximately 126 mm in length having the fuel element disposed at
opposite ends. The edge of the wrapper 42 extends beyond the
abutment point of the fuel substrate unit 32 and the tobacco
section 87. The 2-up tobacco/fuel unit is conveyed to a tipping
unit 92 such as a Max R-3 available from Korber.
Filter material, such as non-woven polypropylene web, is formed
into a continuous rod using a web feeder and KDF (90) filter maker
described in U.S. Pat. No. 4,807,809. The continuous filter rod is
cut into 4-up filter segments 97 approximately 80 mm in length. The
4-up filter segments 97 is passed to the tipper 92. In the tipper
92, the 4-up filter segments 97 are cut into 2-up filters 98
approximately 40 mm in length graded and aligned. The 2-up
tobacco/fuel unit 88 is cut at its midpoint through the tobacco
roll segment 82 graded, aligned, and single units are positioned on
opposite sides of a 2-up filter 98. A tipping paper 46 is applied
by the Max R-3 (Korber) to the assembled components, attaching the
2-up filter 98 between the tobacco/fuel units to form a 2-up
cigarette 102. The 2-up cigarette 102 is then cut through the
midpoint of the filter segment 98 to form single cigarette 104.
Alternate cigarettes 104 are rotated 180.degree. to align so that
all of the cigarettes have the same orientation. The cigarettes 104
may then be transferred to an HCF tray filler 106 or into an
accumulator such as a Resy which may be connected to packaging
equipment.
Referring to FIGS. 4A, 4B and 4C, there is shown a flow diagram of
a preferred method of manufacturing the cigarette embodiment of the
present invention illustrated in FIG. 3 and 1A. Again the method
involves separately manufacturing the various cigarette components,
and combining the individually prepared components in a specified
sequence. The method illustrated in FIGS. 4A, 4B and 4C is a
simplified method.
The jacketed fuel element 52 is prepared as previously described
with the method illustrated in FIG. 2, and cut into 72 mm or 6-up
lengths, and fed into a Max 1 tipper unit 200, available from
Korber.
The substrate rod 50 is formed by providing a reconstituted tobacco
cast sheet material as described in Example 2 herein. The cut
filler material is formed into a continuous rod and overwrapped
with a wrapper using a cigarette making machine 202 such as a
Protos, available from Korber, and cut into rod lengths of 62 mm or
2-up lengths, and transferred to a hopper of the Max 1 Unit
200.
In the tipper unit 200, the 72 mm jacketed fuel rods are cut into
lengths of about 12 mm to form jacketed fuel elements 18. As
described previously, the jacketed fuel elements 18 are combined
with substrate 50 using an overwrap 32, similarly to the method of
FIG. 2. The overwrap 32 is approximately 74 mm in length, and is
applied so that its edges are spaced approximately 6 mm from the
free ends of each of the jacketed fuel elements 18, to form a 2-up
fuel substrate section 65.
Preferably, simultaneously with the manufacture of the
fuel/substrate section 65, tobacco section 34 (FIG. 3) of the
cigarette 5 is being made, as shown in FIG. 4B. A continuous
tobacco rod is formed on a cigarette making machine 71 such as a
Protos VE/SE available from Korber using a cut filler material such
as tobacco, reconstituted tobacco or the like. The continuous
tobacco rod is cut into lengths of 80 mm (4-up) forming tobacco
rolls or rods 70.
Filter material, such as a low efficiency cellulose acetate tow, is
formed into a continuous rod using a KDF filter making machine 300,
and cut into 4-up filter segments 97, approximately 80 mm in
length.
The 4-up tobacco rods 70 and the 4-up filter segments 97 are
transferred to a combining apparatus 61, such as a Mulfi,
consisting of a GC unit 62 and a KDF-2D unit 63 available from
Korber. The tobacco rod 70 and filter segments 97 are cut into 40
mm lengths, and are alternately positioned in the GC unit, graded
and aligned, and transferred to the KDF-2D unit. There they are
overwrapped, and cut into 2-up tobacco filter sections 206, about
80 mm in length. The 2-up tobacco filter sections have a 40 mm
center filter segment and 20 mm tobacco segments on each end.
As shown in FIG. 4C, the 2-up tobacco filter unit 206 and the 2-up
fuel substrate section 65 are transferred to a second tipper unit
208 (See FIG. 4C) such as a Max 2, available from Korber. The 2-up
fuel substrate sections 65 are cut at approximately their
midpoints, and graded, and aligned with a single fuel substrate
section, where they are spaced and positioned at opposite ends of a
tobacco filter section 206, with the substrate adjacent the tobacco
section. The aligned components are overwrapped with a tipping
material 49, RJR Type 1000011, to form a 2-up cigarette 202. The
2-up cigarette is then cut at approximately the midpoint of the
filter to form a single cigarette 104. Alternate cigarettes are
rotated 180.degree. so that all of the cigarettes have the same
orientation. The cigarettes may be transferred to a HCF tray
filler, or to an accumulator such as a Resy, which may be connected
to standard cigarette packaging equipment.
The present invention will be further illustrated with reference to
the following examples which aid in the understanding of the
present invention, but which are not to be construed as limitations
thereof. All percentages reported herein, unless otherwise
specified, are percent by weight. All temperatures are expressed in
degrees Celsius.
EXAMPLE 1
Preparation of Components
Jacketed Fuel Rod
A jacketed fuel rod approximately 7.5 mm in diameter, including a
carbonaceous fuel rod and an insulating material is prepared by
directly extruding the carbonaceous fuel rod into a multilayer
glass fiber/tobacco paper ribbon in accordance with the process
described in U.S. patent application Ser. No. 07/856,239, filed 25
Mar., 1992. The jacketed fuel rod is cut into lengths of about 72
mm.
Carbonaceous Fuel Rod
The carbonaceous fuel rod having an apparent (bulk) density of
about 1.02 g/cc is prepared from about 73.4 parts hardwood pulp
carbon having an average particle size of 12 micron diameter, 10
parts ammonium alginate (Amoloid HV, Kelco Co.), 0.2 parts Na.sub.2
CO.sub.3, 8.4 parts graphite about 8 microns in particle size, 3
parts Ca.sub.2 CO.sub.3 powder, and 5 parts, ball-milled American
blend tobacco.
The hardwood pulp carbon is prepared by carbonizing a non-talc
containing grade of Grande Prairie Canadian kraft hardwood paper
under nitrogen blanket, increasing the temperature in a step-wise
manner sufficient to minimize oxidation of the paper, to a final
carbonizing temperature of at least 750.degree. C. The resulting
carbon material is cooled under nitrogen to less than 35.degree.
C., and then ground to fine powder having an average particle size
of about 12 microns in diameter.
The finely powdered hardwood carbon is dry mixed with the ammonium
alginate binder, levulinic acid and the tobaccos, and then a 3% wt.
aqueous solution of Na.sub.2 CO.sub.3 is added to provide an
extrudable mixture, having a final sodium carbonate level of about
0.9 parts.
The carbonaceous fuel rods are extruded using a screw extruder from
the mixture having a generally cylindrical shape about 4.2 mm in
diameter, with size (6) equally spaced peripheral grooves (about
0.5 mm wide and about 1 mm deep) with rounded bottoms, running from
end to end. The extruded rods have an initial moisture level
ranging from about 36-38 weight percent.
Jacket Material
The jacket material is composed of 2 layers of Owens-Corning
C-glass mat, each about 1 mm thick prior to being compressed by a
jacket forming machine (e.g., such as that described in U.S. Pat.
No. 4,807,809), and after formulation, each being about 0.6 mm
thick. Sandwiched between the two layers of C-glass is one or two
sheets of reconstituted tobacco paper, Kimberly-Clark's
P-3510-96-2. A cigarette paper, designated P-3122-153 from
Kimberly-Clark, overwraps the outer layer. The reconstituted
tobacco paper sheet, is a paper-like sheet containing a blended
tobacco extract. The width of the reconstituted tobacco sheets
prior to forming is about 17 mm, and the width of the cigarette
paper outer sheet is about 25.5 mm. The seam adhesive used for the
outer wrap can be a cold seam adhesive CS 1242, available from RJR
Packaging, R. J. Reynolds, Winston-Salem, N.C.
Substrate Tube
A continuous substrate rod about 7.5 mm in diameter is formed from
a wide, highly embossed, 36 gsm, about 7 inch wide web of paper
containing 25% calcium sulfate available from Kimberly-Clark (K-C)
as P3284-19, e.g., on a modified KDF-2 rod forming apparatus. The
substrate rod is overwrapped with a paper/foil laminate having a
width of about 24.5 mm, the foil being a continuous cast 0.0005
aluminum foil, and the paper being a Simpson Paper Co. ("Simpson")
RJR 002A paper. The lamination adhesive is a silicate adhesive, No.
0650-05-0051, available from RJR Packaging. A center line adhesive,
cold adhesive CS 1242M, available from RJR Packaging, is spray
applied to the laminate, to hold the substrate in place within the
wrap. The seam is sealed with hot melt adhesive 444-227, from RJR
packaging.
The overwrapped rod is cut into 60 mm segments. Approximately 900
mg of an aerosol forming material comprising glycerin, propylene
glycol, and flavorants, such as tobacco extract, is applied to the
web during formation of the continuous substrate rod. The substrate
segment is cut into substrate plugs about 10 mm in length and
overwrapped with a Simpson RJR 002A/0005 foil laminate described
above, having a width of about 25.5 mm. The plugs are placed at
alternate intervals of 10 and 12 mm along the tube. The plugs are
adhered to the tube by corresponding application of hotmelt
adhesive No. 448-37A, RJR Packaging. The seam is sealed with hot
melt adhesive 444-227, from RJR Packaging.
The continuous tube is cut into substrate void tube sections about
42 mm in length having a center void about 12 mm, two substrate
plugs 10 mm wide, and void space at each end of about 5 mm in
width.
Tobacco Section
A reconstituted tobacco cut filler prepared as described in U.S.
patent application Ser. No. 07/710,273 filed Jun. 14, 1991, is
formed into a rod about 7.5 mm in diameter and overwrapped with
paper, e.g. KC 646, 25.5 mm in width, using a Protos cigarette
making machine, using a standard tipping adhesive. The overwrapped
tobacco roll is cut into 120 mm length segments.
A tobacco paper rod about 7.5 mm in diameter is formed from a
medium embossed, 127 mm wide web of tobacco paper designated as
P-144-GNA-CB available from Kimberly-Clark, e.g., using a rod
forming apparatus such as that disclosed in U.S. Pat. No.
4,807,809. The rod is overwrapped with a KC paper P1487-184-2,
about 25 mm wide, and cut into 80 mm length segments.
The tobacco roll and tobacco paper segments are cut into 40 mm and
20 mm segments respectively and are aligned in an alternating
arrangement and overwrapped with a wrapper of KC 646 paper, 25.5 mm
in width, using a center line hot melt adhesive 448-37A, RJR
Packaging, and a seam adhesive, 448-195K hot melt, RJR Packaging.
The combined tobacco roll/tobacco paper assembly is cut into a 2-up
tobacco section 60 mm in length having a 40 mm tobacco roll center
segment and 10 mm tobacco paper segment on each end of the tobacco
roll segment.
Filter
A polypropylene filter rod about 7.5 mm in diameter is formed from
a PP-100 mat, about 260 mm wide, available from Kimberly-Clark and
overwrapped with a 25.5 mm width web of paper P1487-184-2,
available from Kimberly-Clark, e.g., using the apparatus described
in U.S. Pat. No. 4,807,809, and hot melt 448-195K seam adhesive.
The overwrapped rod is cut into 80 mm length segments.
CIGARETTE ASSEMBLY
Fuel Substrate Section
A jacketed fuel rod is cut into fuel elements 12 mm in length. Two
fuel elements are positioned on opposite sides of a substrate void
tube section, and aligned. These components are overwrapped with a
wrapper about 26.5 mm in width and about 54 mm in length,
comprising a paper/foil/paper laminate, comprising Ecusta 15456
paper/continuous cast 0.0005 foil/Ecusta 29492 paper, which are
laminated to the foil using Airflex Adhesive 465. The laminate is
adhered to the jacketed fuel and the substrate void tube assembly,
by cold adhesive MT-8014, RJR Packaging, applied to the entire
inner surface of the laminate. The wrapper overwraps the substrate
tube and extends to within about 6 mm of the free end of each fuel
element to form a 2-up fuel substrate section.
Tobacco Fuel Unit
A 2-up fuel/substrate section is cut at its midpoint and positioned
on opposite sides of a 2-up tobacco section and aligned so that the
void end of each fuel-substrate section is adjacent and abuts the
tobacco paper plugs at each end of the 2-up tobacco section. The
assembled components are overwrapped with Ecusta E30336 paper,
about 70 mm in length and about 26 mm wide. The wrapper is adhered
to the fuel substrate section and the tobacco section with MT-8009
adhesive, RJR Packaging, to form a 2-up tobacco-fuel unit
approximately 126 mm in length.
Cigarette
A 2-up tobacco-fuel unit is cut at its midpoint and positioned on
opposite sides of a 2-up filter unit and aligned so that the
tobacco roll end of a single tobacco-fuel unit is adjacent and
abuts the 2-up filter. The assembled components are overwrapped
with a tipping wrapper, RJR tipping code No. 1000011, approximately
50 mm in length and about 26 mm in width which extends
approximately 5 mm over each of the junctures between the 2-up
filter and each tobacco-fuel unit. The wrapper is adhered over its
entire area to the assembled components with an adhesive MT-8009,
RJR Packaging, 100% coverage, to form a 2-up cigarette. The 2-up
cigarette is cut at approximately its midpoint (i.e., the midpoint
of the 2-up filter) to form a single cigarette.
EXAMPLE 2
Preparation of Components
Jacketed Fuel Rod
A fuel element about 4.2 mm in diameter, and having an apparent
(bulk) density of about 1.02 g/cc is prepared from about 72.6 parts
hardwood pulp carbon having an average particle size of 12 .mu.m in
diameter, 10 parts ammonium alginate (Amoloid HV, Kelco Co.), 8.4
parts graphite powder, 1 part Na.sub.2 CO.sub.3, 3 parts
CaCO.sub.3, and 5 parts ball-milled American blend tobacco.
The hardwood pulp carbon is prepared by carbonizing a non-talc
containing grade of Grande Prairie Canadian kraft hardwood paper in
an inert atmosphere, increasing the temperature in a step-wise
manner sufficient to minimize oxidation of the paper, to a final
carbonizing temperature of at least 750.degree. C. The resulting
carbon material is cooled in the inert atmosphere to less than
35.degree. C., and then ground to fine powder having an average
particle size (as determined using a Microtrac Analyzer, Leeds
& Northrup) of about 12 mm in diameter.
The finely powdered hardwood carbon is dry mixed with the graphite,
CaCO.sub.3, ammonium alginate binder, levulinic acid and the
tobaccos, and then a 3 weight percent aqueous solution of Na.sub.2
CO.sub.3 is added to provide an extrudable mixture, having a final
sodium carbonate level of about 1 part.
A jacketed fuel rod is prepared by directly extruding the
carbonaceous fuel rod into a multilayer glass fiber/tobacco paper
ribbon in accordance with the process described in U.S. patent
application Ser. No. 07/856,239, filed 25 Mar., 1992. The jacketed
fuel rod is cut into lengths of about 72 mm.
Jacket Material
The jacket material is composed of 2 layers of Owens-Corning
C-glass mat, each about 1 mm thick prior to being compressed by a
jacket forming machine (e.g., such as that described in U.S. Pat.
No. 4,893,637), and after formulation, each being about 0.6 mm
thick. Sandwiched between the two layers of C-glass is one or two
sheets of reconstituted tobacco paper, Kimberly-Clark's
P-3510-176-60. A cigarette paper, designated No. 15456, from Ecusta
overwraps the outer layer. The reconstituted tobacco paper sheet,
is a paper-like sheet containing a blended tobacco extract. The
width of the reconstituted tobacco sheets prior to forming is about
17 mm, while the width of the cigarette paper outer sheet is about
25.5 mm. The seam adhesive used for the outer wrap can be a cold
seam adhesive CS 1242, available from RJR Packaging, Winston-Salem,
N.C.
Substrate Rod
A cast sheet material is provided by casting an aqueous slurry of
components from a headbox at a nominal thickness of about 30 mils
onto a heated stainless steel belt. The cast slurry has a solids
content of about 12 percent. The slurry is provided by dispersing
in water about 32 parts of tobacco pulp in the form of extracted
stems and laminae, about 8.75 parts flue-cured tobacco laminae,
about 8.75410 parts burley tobacco laminae, and about 14.5 parts
extracted burley stems. As such, a slurry having about 1 part
tobacco and about 8 parts water is provided. The resulting slurry
is refined using a disc refiner, and transferred to a mixer. To the
slurry, which includes about 32 parts tobacco, is added about 55
parts glycerin; about 6 parts of the type of tobacco extract
described in Col. 11, lines 5-37 of U.S. Pat. No. 5,159,942 to
Brinkley et al diluted in water in an amount of about 8 parts
extract and about 92 parts water; and about2 parts of a commercial
flavorant, such as Lovage flavorant. However, the selection and
relative amounts of those components, such as flavors and tobacco
extracts, can vary as desired to provide the desired organoleptic
characteristics.
The resulting slurry is mixed to yield a consistent character.
Then, about 5 parts ammonium alginate available as Amoloid HV from
Kelco Division of Merck & Co., Inc. is added to the slurry. The
resulting slurry is thoroughly mixed at ambient conditions using a
Breddo Likwifier high shear propeller mixer. The slurry is cast
onto a stainless steel belt heated at about 220.degree. F. The
dried cast slurry is diced and cut into cut filler size of about 25
cuts per inch. The cut filler is conditioned to yield a substrate
having a moisture content of about 15 percent and a thickness of
about 6 mils.
The cast sheet substrate material is formed into rods using a rod
forming apparatus such as a Protos from Korber. The substrate rod
includes a paper/aluminum foil laminate overwrap having a width of
about 25.5 mm, the foil being cast aluminum, 0.0005 inches thick,
and the paper is available as Ref. 29492 from Ecusta. The laminate
is formed with a silicate adhesive, designated as RJR LAM-1-5001,
available from RJR Packaging. The laminated paper is formed into a
tube (with the foil on the inside) by lap joining using a CS1242
adhesive, available from RJR Packaging. The overwrapped rod is cut
into 62 mm long segments. The 62 mm rod weighs about 800 mg.
Tobacco Section
A reconstituted tobacco cut filler prepared as described in U.S.
patent application Ser. No. 07/710,273 filed Jun. 14, 1991, is
formed into a rod about 7.5 mm in diameter and overwrapped with
paper, e.g. Ecusta No. 15456, 25.5 mm in width, using a Protos
cigarette making machine, using a standard seam adhesive. The
overwrapped tobacco roll is cut into 80 mm length segments.
Filter
A cellulose acetate filter rod about 7.5 mm in diameter is formed
from a 10/35,000 Denier cellulose acetate tow containing 0.6%
triacetin, and overwrapped with a web of 646 plug wrap, about 25.5
mm in width, available from Kimberly-Clark or Ecusta on a standard
filter rodmaker. The overwrapped rod is cut into 80 mm length
segments.
Cigarette Assembly
Fuel Substrate Section
A jacketed fuel rod is cut into fuel elements 12 mm in length. Two
fuel elements are positioned on opposite sides of a substrate
section and aligned. These components are overwrapped with a
wrapper about 26.5 mm in width and about 74 mm in length,
comprising a paper/foil/paper laminate, comprising Ecusta 99952
paper/continuous cast 0.0005 inch thick aluminum foil/Ecusta 99951
paper, which are laminated to the foil using RJR LAM-5001 (1.0
lbs/ream) available from RJR Packaging. The laminate is adhered to
the jacketed fuel and the substrate assembly, by cold adhesive
MT-8009B, RJR Packaging, applied to the entire inner surface of the
laminate. The wrapper overwraps the substrate tube and extends to
within about 6 mm of the free end of each fuel element to form a
2-up fuel substrate section.
Tobacco/Filter Section
An 80 mm tobacco roll and an 80 mm filter segment are cut into 40
mm sections, and are alternately aligned and overwrapped with a
wrapper about 25.5 mm in width, e.g., Type 646 from Kimberly-Clark,
using a standard seam adhesive. The resulting rod is cut into 80 mm
segments having a 40 mm center filter segment, with 20 mm tobacco
rolls on opposite ends to form a 2-up tobacco filter section.
Cigarette
A 2-up fuel-substrate section is cut at its midpoint and positioned
on opposite sides of a 2-up tobacco filter section, and aligned so
that the substrate end of a single fuel-substrate unit is adjacent
and abuts the tobacco roll of the 2-up tobacco-filter section. The
assembled components are overwrapped with a tipping wrapper, RJR
tipping code No. 1000011, approximately 90 mm in length and about
26 mm in width which extends approximately 5 mm over each of the
junctures between the 2-up tobacco-filter and each fuel-substrate
unit. The wrapper is adhered over its entire area to the assembled
components with an adhesive MT-8009 (RJR Packaging) 100% coverage,
to form a 2-up cigarette. The 2-up cigarette is cut at
approximately its midpoint (i.e., the midpoint of the 2-up filter)
to form a single cigarette.
The present invention has been described in detail, including the
preferred embodiments thereof. However, it will be appreciated that
those skilled in the art, upon consideration of the present
disclosure, may make modifications and/or improvements on this
invention and still be within the scope and spirit of this
invention as set forth in the following claims.
* * * * *